Novel proteins associated with risk for coronary heart disease or stroke among postmenopausal women identified by in-depth plasma proteome profiling

Abstract

BackgroundCoronary heart disease (CHD) and stroke were key outcomes in the Women's Health Initiative (WHI) randomized trials of postmenopausal estrogen and estrogen plus progestin therapy. We recently reported a large number of changes in blood protein concentrations in the first year following randomization in these trials using an in-depth quantitative proteomics approach. However, even though many affected proteins are in pathways relevant to the observed clinical effects, the relationships of these proteins to CHD and stroke risk among postmenopausal women remains substantially unknown.MethodsThe same in-depth proteomics platform was applied to plasma samples, obtained at enrollment in the WHI Observational Study, from 800 women who developed CHD and 800 women who developed stroke during cohort follow-up, and from 1-1 matched controls. A plasma pooling strategy, followed by extensive fractionation prior to mass spectrometry, was used to identify proteins related to disease incidence, and the overlap of these proteins with those affected by hormone therapy was examined. Replication studies, using enzyme-linked-immunosorbent assay (ELISA), were carried out in the WHI hormone therapy trial cohorts.ResultsCase versus control concentration differences were suggested for 37 proteins (nominal P < 0.05) for CHD, with three proteins, beta-2 microglobulin (B2M), alpha-1-acid glycoprotein 1 (ORM1), and insulin-like growth factor binding protein acid labile subunit (IGFALS) having a false discovery rate < 0.05. Corresponding numbers for stroke were 47 proteins with nominal P < 0.05, three of which, apolipoprotein A-II precursor (APOA2), peptidyl-prolyl isomerase A (PPIA), and insulin-like growth factor binding protein 4 (IGFBP4), have a false discovery rate < 0.05. Other proteins involved in insulin-like growth factor signaling were also highly ranked. The associations of B2M with CHD (P < 0.001) and IGFBP4 with stroke (P = 0.005) were confirmed using ELISA in replication studies, and changes in these proteins following the initiation of hormone therapy use were shown to have potential to help explain hormone therapy effects on those diseases.ConclusionsIn-depth proteomic discovery analysis of prediagnostic plasma samples identified B2M and IGFBP4 as risk markers for CHD and stroke respectively, and provided a number of candidate markers of disease risk and candidate mediators of hormone therapy effects on CHD and stroke.Clinical Trials RegistrationClinicalTrials.gov identifier: NCT00000611

Protein Biomarkers of Cardiovascular Disease and Mortality in the Community

“…We demonstrate multiple new associations of protein biomarkers that regulate metabolic and inflammatory pathways with clinical outcomes using a multiplexed high‐throughput platform. Previous proteomics approaches among large cohorts have been predominantly focused on CVD case‐control designs 3, 12. We now extend previous promising results and test the association of targeted proteomic biomarkers with incident CVD events and death in the community.…”

“…Adipsin has been shown to regulate inflammation in adipose tissue and may improve beta‐cell function in diabetes mellitus 11, 23, 24. Among women, adipsin is correlated with metabolic parameters, including body mass index, insulin resistance, and carotid atherosclerosis,3, 12, 25 but it has not been linked to adverse CVD outcomes previously. Last, resistin is an adipokine that impairs insulin action and is thought to represent a mechanistic link of obesity with diabetes mellitus 17, 18, 26.…”

Menopausal Hormone Therapy and Cardiovascular Disease Risk: Utility of Biomarkers and Clinical Factors for Risk Stratification

“…Levels of these proteins increased following HT initiation, suggesting that these changes may partly explain effects of HT on CHD and stroke (47 ).…”

Overview of Current Proteomic Approaches for Discovery of Vascular Biomarkers of Atherosclerosis

“…In the latest years, proteomics has been applied to plasma/serum to identify early diagnostic markers in relation to several cerebro-cardiovascular pathologies such as stroke (Allard et al, 2004;Kiga et al, 2008;Brea et al, 2009;Prentice et al, 2010), acute coronary syndrome (Mateos-Cáceres et al, 2004;Dardé et al, 2010), angiographic coronary disease (Donahue et al, 2006), acute myocardial infarction (AMI) (Distelmaier et al, 2009), coronary heart disease (CHD) (Prentice et al, 2010), coronary artery bypass grafting (CABG) , aortic atherosclerotic plaque (Tabibiazar et al, 2006), and peripheral arterial disease (Wilson et al, 2007). Moreover, differential proteomic analysis has been addressed to elucidate effects on plasma proteome of different pharmacological treatments (AlonsoOrgaz et al, 2006;López-Farré et al, 2007).…”

“…Moreover, differential proteomic analysis has been addressed to elucidate effects on plasma proteome of different pharmacological treatments (AlonsoOrgaz et al, 2006;López-Farré et al, 2007). In this regard, the most applied proteomic methodologies were gel electrophoresis coupled to mass spectrometry analyses followed by gel free proteomic approaches such as LC MS/MS (Donahue et al, 2006;Wilson et al, 2007;Prentice et al, 2010) and microarrays (Tabibiazar et al, 2006). Almost all of these analytical approaches were preceded by one or more fractionation steps, mainly immunoaffinity depletion of the most abundant plasma protein species and ion exchange chromatography, to reduce the high complexity of plasma samples in terms of both number and dynamic range of protein species.…”